The invention relates to a thread guidance means for feeding a plurality of threads to a textile machine working the threads, having a plurality of thread carriers running in tandem along an endless path, the filaments being fed from supply spools through movable thread guides to the thread carriers and a device being provided for the prevention of any twisting of the threads.
Certain textile machines, such as flat-bed knitting machines for example, having carriages circulating on an endless path (German OS No. 1,585,454), circular knitting machines with revolving mechanisms (German OS No. 2,540,498), warp knitting machines or undulating shed looms (German OS No. 2,450,020) have endless paths of movement on which a plurality of units run in tandem, which consist each of a thread carrier, a supply spool, a thread guide, a gripper means and, in case of necessity, also a thread clipper. Since not enough space is available for the transport of a large number of supply spools and great weights have to be transported, only a few of these units can be provided on the textile machine. Furthermore, empty supply spools can be replaced only with the textile machine shut down, and this considerably reduces production capacity.
Thread guidance systems of the kind described in the beginning have therefore become known (German OS Nos. 2,064,227 and 2,351,741) which have stationary supply spools for the threads being fed to a knitting machine, warp knitting machine or an undulating shed loom. To prevent the twisting of the threads, an endless path of movement in a kind of figure eight is provided for the thread carriers, by which it is brought about that the threads alternately twist in the one direction and in the opposite direction as the thread carriers circulate, so that after each full circuit of all thread carriers, the desired starting position can be recovered and no permanent or constantly increasing twist of the threads is possible. It is true that the parts of the threads that are between the thread carriers and the eyelet bar always touch one another and therefore rub against one another when the threads are drawn from the supply spools and fed to the textile machine. The consequence of this is differing thread tensions and damage to the threads as they are drawn from the supply spools, and this is undesirable.
Furthermore, thread guidance systems are already known (German OS No. 2,701,652) in which the twisting of the threads is prevented by the fact that, during successive circuits of the thread carriers on an endless, O-shaped path, the threads are alternately fed to the thread carriers from the one and the other side of a surface laid through a work area and a return area of the circuit. In this thread guidance system, the threads can be kept out of contact during their withdrawal from the supply spools and their delivery to the textile machine. Contact and friction between the threads, however, are possible during the return of the thread carriers, and experimenta have shown that this is sufficient to produce visible tufts and streaks, especially when threads of different color and/or character are to be used.
Lastly, contact and rubbing of the threads against one another can be reduced if in the case of thread guidance systems of the kind described in the beginning, thread guiding eyelets are provided between the sypply spools and the thread carriers, and these are disposed on two eyelet bars and during operation are constantly rocked back and forth about a common axis (German OS No. 2,064,227). This rocking movement, however, is not sufficient to completely prevent contact and friction when a large number of threads are being fed.
It is the object of the invention, therefore, to improve the thread control system described in the beginning in such a manner that contact between individual threads can be completely prevented. Another object is to prevent contact between the threads even when a very large number of threads are to be fed to the textile machine.
The invention consists in a thread guidance system for the feeding of a plurality of threads to a textile machine working the threads, having a plurality of thread carriers running in tandem in an endless circuit, the threads being carried from supply spools through movable thread guides to the thread carriers, a system for the prevention of the twisting of the threads being provided, and the thread guides being movable individually and independently of one another.
The invention sets out from the knowledge that contact and friction between the threads can be completely prevented if the thread guides, such as thread eyelets for example, instead of being moved together in sets (German OS No. 2,064,227) are moved singly and independently of one another on paths whose form on the one hand depends largely on the textile machine involved in the particular case and on the number of threads to be fed, but on the other hand always can easily be determined even when the number of threads to be fed is very large.
The thread guidance system of the invention can be used to special advantage in knitting machines pursuant to German OS No. 2,531,762 and in combination with apparatus pursuant to German OS No. 2,701,652. The term "threads", as used herein, is intended to cover all kinds of threads, as well as thread-like, ribbon or strip materials, especially glass fibers or metal wires, which can be worked by textile machines of the kind described.
Additional advantageous features of the invention will be found in the subordinate claims.